Our recent cold weather rendered many shrubs droopy, some trees damaged and a perennial or two dead.
Yet there's hope for the shrubs and trees. Although the leaves on evergreen shrubs such as rhododendrons and azaleas may have drooped and curled, the plants are reacting to the cold temperatures, not dying.
Once the weather warms up, many of the leafy evergreens plants will perk up too. And if we have another cold spell, the same evergreens have gotten a chance to acclimate to cold weather and will most likely come through in good shape.
If by chance your rhododendrons and azaleas have suffered damage in the freezing weather, it's best now to attend to those broken or cracked limbs. By removing the impacted wood, you can eliminate areas for rot and disease to take over. What to cut? Look for damaged twigs and limbs and cut them back to the next healthy and strong wood or bud. Keep your cuts close to the trunk of the plant so that you do not leave a stub or snag. And cut near the next healthy bud, but not too close. The bud can dry out and die if its tender base is exposed.
This is also a good time to take out any dead wood that you might have missed during an earlier pruning. The February issue of Fine Gardening has some good advice from contributing editor Lee Reich, who reminds us to practice maintenance pruning, "thoughtfully cutting back tips, branches, limbs and stems" to encourage healthy growth. In addition to removing dead wood, Reich encourages us to thin out stems that have become crowded and to remove suckers at their growth points.
While you're at it, you might want to consider pruning your butterfly bushes, elderberries, Japanese spireas, smoke bushes, St. John's worts and any other late-flowering shrubs that can use a cut before spring growth starts. Don't forget to take those butterfly bushes to the ground for the best new growth.
When dealing with storm-damaged trees, you might want to pay attention to the limbs. If they are bent but not cracked, don't cut them off right away. If you remove extra weight from the limb, such as snow or ice or other debris, there's a good chance the limb will straighten out over time. Again, if you are taking a large limb down, cut back to the trunk or a major side limb and make the cut clean to prevent rot from setting in. Young trees have a better chance of revival than most older trees, particularly those that show little regrowth from the previous year or that have been previously damaged.
To give your recovering trees and shrubs a boost, apply nitrogen fertilizer around the drip line area in early spring.
In the worst case, if the chilling temperatures killed your shrubs and plants, it's probably a situation where the plant didn't have time to go into complete dormancy before the cold weather hit. Woody plants can get "caught" with too much moisture in their trunks and limbs. This is often the case with azaleas and smaller rhododendrons. Oregon State University researchers have found this damage to take place commonly on the south and southwest side of the shrubs, spots on the plants that are not well acclimated for the cold because of their sun exposure.
If you have advance warning of dropping temperatures, you can protect smaller woody perennials that haven't entered dormancy by mounding bark dust, wood chips or sawdust around their trunks. You can wrap the trunks of trees and larger bushes. OSU recommends painting the trunks with a blend of white exterior latex paint mixed one part water to one part paint or a whitewash. These precautions only help before the weather starts.
If you have lost a tree and are considering replacing it, you might want to choose one that isn't as susceptible to ice and storms. Conifers resist most storm damage better than deciduous tree species. Spruces and firs can take more storm action than pines.
Cathy Peterson belongs to the Clatsop County Master Gardener Association. "In the Garden" runs weekly in Coast Weekend. Please send comments and gardening news to "In the Garden," The Daily Astorian, P.O. Box 210, Astoria, OR 97103 or online to firstname.lastname@example.org